Background/Purpose: In a previous study it was demonstrated that, in patients with systemic sclerosis (SSc) the cumulative number of micro-haemorrhages (MH) and micro-thrombosis (MT) (the so called NEMO score), observed in nailfold videocapillaroscopy (NVC), was strongly predictive of disease activity (DA). [1].The present study is aimed at validating NEMO score as predictor of DA in different cohorts of patients.

Methods: The NEMO score, total number of giant capillaries (GC) and mean number of capillaries (Cs) were computed by eight finger NVC in 122 patients with SSc referring to the Rheumatic Disease Unit of the ‘Istituto G.Pini’ of Milan, where the preliminary study had been carried out (internal validation). The same procedure was performed in 97 patients collected in a different centre, i.e., the Rheumatic Dept. of the II University of Naples (external validation). In all of the patients DA was assessed at the same time of NVC performance by means of the European Scleroderma Study Group (ESSG) scoring system.

Results: Demographic and clinical characteristics of the patients were summarised in Table 1.

number

of patients

male/

female

patients with

lcSSc/dcSSc

age (years)

median (range)

disease duration

median (range)

patients with a

ESSG score≥3

Milan Cohort

122

8/114

60/62

52 (17-82)

4 (0-28)

57

Naples Cohort

97

9/88

72/25

55 (19-79)

6 (0-36)

30

All patients

219

17/202

132/87

53 (17-82)

5 (0-36)

87

lcSSc= limited cutaneous SSc; dcSSc=diffuse cutaneous SSc. Table 2: Main statistical results obtained by the analysis of the two cohorts.

correlation* between

NEMO and ESSG score

correlation* between

GC and ESSG score

NEMO ROC^ curve for ESSG score≥3

sens./spec. of NEMO>8

for ESSG score ≥3

Milan Cohort

R=0.69; p<0.0001

R=0.30; p<0.001

AUC°= 0.926

84.2/92.3

Naples Cohort

R=0.76; p<0.0001

R=0.39; p<0.0005

AUC°= 0.930

93.3/76.1

*by Spearman Rank correlation; ^ROC=receiver operating characteristic; °AUC=area under the curve; sens.=sensitivity; spec.= specificity. In a logistic regression model were NEMO, GC e Cs were considered the independent variables and a ESSG≥3 the dependent variable, only NEMO score showed to have a significant predictive value for DA.

Conclusion: This validation study confirms that the presence of a certain number of MH plus that of MT in eight finger NVC may represent a simple screening method to predict the presence of DA in patients with SSc. References. 1. Sambataro D, et al. Arthritis Res & Ther 2014;16:462.